Fiber



Patented June 11, 1940 UNITED STA S PATENT OFFICE FIBER Earle 0.Whittier and Stephen P. Gould, Washington, D. 0., dedicated to the freeuse of the People of the United States of America No Drawing. Originalapplication August 12,

1937, Serial No. 158,822. Divided and this application May 19, 1938,Serial No. 208,829

3 Claims. (Cl. 1854) (Granted under the act of March 3, 1883, as amendedApril 30, 1928; 370 0. G. 757) This application is made under the act ofMarch 3, 1883, as amended by the act of April 30, 1928, and theinvention herein described and claimed, if patented, may be manufacturedand used by or for the Government of the United States for governmentalpurposes without the payment to us of any royalty thereon.

This application is a division of the one filed by us on August 12,1937, bearing Serial No. 158,822.

We hereby dedicate the invention herein described to the free use of thePeople of the United States of America to take effect on the granting ofa patent to us.

Our invention deals with fibers made from casein.

The objects of our invention are to produce dispersions of casein (mixedusually with plasticizers and salts), which can be extruded into fibershaving the requisite characteristics of strength, water resistance,flexibility, fire-resistance, and softness necessary to make themsuitable for use in textiles, and are valuable as substitutes for W001and other fibers.

In forming dispersions suitable for extrusions, the casein is dissolvedor dispersed in a solution of some protein solvent. Plasticizers, saltsfor increasing the strength and water-resistance, and fireproofingingredients may be incorporated in the dispersion.

Our fibers may be made fire-retardant as illustrated by the followingexamples:

Example 1 Casein--- 24 Water 169.3 Sodium aluminate 0.63 Sodiumhydroxide solution (2N) 6 (This composition is improved by the additionof plasticizers) This solution is extruded into a bath comprising 3pts.-phosphoric acid, 5-formaldehyde and 92ethanol. Thus, aluminumphosphate is formed in the fibers, and acts as a fire-retardant. Thefibers were subjected to the application of a flame, and they charredonly slightly. We also found that their water-repellency was excellent.

phosphate is again formed as the filaments are precipitated. They alsoshow fire retardance. The fibers are excellent with respect toflexibility, water resistance, etc., as Well.

Example 3 Casein 24 Water 204.5 Oleic acid 5 Sodium aluminate 0.5 Sodiumhydroxide solution (2N) 1 Sodium silicate solution 5 The bathcomposition may comprise the same ingredients as in Example 2. Thefibers exhibit considerable fire retardance, and in addition, otherdesirable properties, as set forth under Example 2. As a variation fromthe above procedure, the sodium aluminate can be omitted, and thesolution extruded into a bath comprising acetic acid and calciumchloride. The filaments, however, are somewhat less satisfactory.

Dispersion and bath temperatures in the foregoing examples are usually70 C., but other temperatures ranging/from 50 C. up, may be employed aswell.

It will be understood that our invention is not restricted to any of theexamples given, as proportions, constituents, and substitutes may bevaried over a wide range.

It is also to be understood that greater fire resistance may be obtainedby an increase in the inorganic constituents, but this often results inan increase in viscosity so that extrusion is more diflicult.

Having thus described our invention what we claim for Letters Patent is:

1. A method for producing fire retardant and water resistant fibers,which comprises subjecting a dispersion comprising casein and sodiumsilicate having an alkaline reaction in the form of fine streams to theaction of a bath comprising an acid and calcium chloride, wherebycalcium silicate is formed in the fibers.

2. A method for producing fire retardant and water resistant fibers,which comprises subjecting a dispersion comprising casein and sodiumsilicate having an alkaline reaction in the form of fine streams to theaction of a bath comprising acetg acid and calcium chloride, wherebycal- Ei'um silicate "is --formed'in' the-fibersr--" 3. As an article ofmanufacture, a fire retardant and water resistant fiber, which comprisescasein and calcium silicate.

EARLE O. WHITTIER. STEPHEN, P. scum.

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